Flexible attachment for trolley poles



July 31, 1923.

. 39463244 F. T. BOGARD FLEXIBLE ATTACHMENT FOR TR oLLzY'PoL s Fi ledJan. 29,1923

INVENTOR. "i

BY Q

Patented July 31, 1923.

' titans V or "onktnnn, Gent-rosters,

FLEXIBLE nranefinhur roe --"rnoL nY Pon es.

l -App1ica tion:fi1 d January 29,1923. Serialiio. 615320.

- .c mpa ying d a ings, andto he e11 racters of reference markedthereon, wh chgform .apart of this application 'T-his invention relatesitoiimpro vements in 7 trolley pole construction and is particularly :15an improvementv over thedevice {shoyvn' in -United States Patent$01,371,551; dated March 15th, 1921, on ajtrjolley pola v "The principalobject of the present invention is toprovide a means fornreventing thepole-Wheel from so readllv ninpinglor leaving the 7 Wire at; pressings;splines,

curves and maybe attached to any standa d" trolley pole without making,anyychangies in the latter'other Jthan thezcuttin'g out of a 2 sectionof-the necessany-length..l;.;

A further objectis toprdvidesuc-h,,a de vice as will haveythev greatest'gpossible strength and flexibilitim encompassed in the minimum of spaceandfwhichiorms a com- .3 .plete-I unit of itself; which maylthen-rbeattached to the pole inveryshort order.

Another object is .toiprov1dela simple meansfor-insufinggthamhe passageofthe current through the attachment Will not be interrupted under anyconditions of operations. I a p A further object of the invention is toproducea simple and inexpensive device and yet onewvhich will beexceedingly effective '7 i have found that the sprlng inorder to givethe best results asto Wear and efficiency of,

40 for the purposes for Which it is designed.

These objects I accomplish by means of such structure and relative'arrangementof parts as Will fully appear by aperusal of the followingspecification and claims. ii In the drawings similar characters ofreference indicate "corresponding parts in the) several views:

. Fig. 1 1s a side elevation of the, attach ,ment, as applied to'atrolley pole.

7 Fig.2 is a sectional view .of' thef attach ment itself. o 5

Referring now more particularly to the characters of reference onthegdravving the; device compnses a pair of long tudinally sp d d Mimitems aud aitlie ems:

be n adapted [to e ins rted. ntofandg ig- ..;1 ly seem to the stan ardbellow. pole :13

by riv in 9 io h r i'se, heot er' s em being sim larly adapted robefixed to. the h p and o e p le t e) piele tang. To

t an if ileces arya cer ain ortien of its, length r m v d," nea the barnshown il t s li f -he e We terns.Will-thereforei e h rein fterreferredft marshte anther-P tem r pective ye i. he-a j it ends f t esiestenish v. j lerg'ed p erheads acwhich farm-steps FRANK '1'. Bosnian,oronirtiiiv'n, oA ronnrn-nssmnon TononnitY'nf. a er-gig e;

P se t n andiever uhiclri a fit e te a dutf -1f, "the length a of thesee her are We. ing, t e; fa S s rin and i11 re iir heraliisurfaee5f thehea s Qu iverdly of the spring fannin th ar a [of cen a t for the. Weldng metawhi h fenns eon inuousarii gejf Pre ads the eorresnei d nseuc1s1na -b ose y Before this eld'ng' iis'idone'ihowe er, a fi iaicopper ablsifiis e tended Betw th stem insielethe pr ng, the nds P s ni throug ho e 9. drille thrni ghithe a i ang the ou rfendsxo eingoutwardly ii -the spr ng-ends h cab -ends1.p trude'-fr m 1 hole semivhatiso th trvvhen th ivve dine peratiqn aforementioned is carried out,the cableends are likevvise'embedded in the Welding- 1e te fth a ab y-t.-tr ang r'prQssseQtnnass ovvnat 1 ese belie After considerableeirperimentation, I

operation should be constructed in-the fol lovvmg manner:

It should be very closely coiled, somewhat greater in diameter at theharp-stem end than at the polestern end."

here rounded or chamfered' as 'shovv'n'at'10',-

and the two parallel sides being 'theouter and inner peripheries of thecoils, While the" outer face is somewhat narrower than the innenasgvvillbe plainly seen in Fig. 2.

In consideringthe action of this spring,

cure by Letters Patent is: I

it is to be understood that it is not used for tension or compressionpurposes, but for bending or oscillating flexibility.

The particular cross-section usedis not only to gain the maximumstrength in the smallest area of length and circumference of spring, butso-that when the spring-coils are brought together on the under sidewith the bending of the spring due to the upward tension of the pole,when the trolley wheel is engaging its wire, the adjacent side-faces 'ofthe under portion of the coils will abut against'each other throughouttheir width,

therebyforming a continuous and compact surface from one'end of thespring to the other, which tends to prevent breakage.

By increasing the diameter of the spring from the pole to the harp end,the resistance of the coils is less atthe outer end, which is adesirable feature, since it insures uniformity of flexible bending fromone end to the other, the principle involved being somewhat sim ilar tothat'of a lever, whioh is made heaviest at its fixedor pivoted end.

From the foregoing description it will be readily seen that I haveproduced such a device as substantially fulfills the objects of theinvention as set forth herein.

While this specification sets forth in detail the present and preferredconstruction of the device, still in practice such deviations from suchdetail maybe resorted to as do not form a departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described my invention, what I claim as new and useful anddesire to se- 1. A flexible attachment for trolley poles comprising apair of separated stems, a spring whose ends project over the adjacentends of the stems, a separate current conducting cable extending betweenthe stems 'inside the spring, the ends of said cable being passed to theoutside of the stems beyond the spring-ends through holes bored 4through said stems, the spring and cable ends being then welded to thestems, the welding-metal being placed about the corners formed betweenthe spring-ends and the surface of the stems outwardly thereof.

2. A flexible attachment for a trolley pole, the latter being out in twotransversely, comprising a pair of separated stems adapted to fit intothe cut ends of the pole, heads on the stems: forming stops for thepole-sections, and a helical spring whose ends project over the headsand welded thereto.

3. A flexible attachment for trolley poles comprising a pair ofseparated stems and a closely coiled helical spring of rectangularcross-section into which the adjacent ends of the stems project, andwhich is welded to the stems. 1

- l. A flexible attachment for trolley poles comprising a pair ofseparated stems, heads on the adjacent ends thereof, and a helicalspring into which the heads partly project, the heads and spring endsbeing then welded together.

5. A flexible attachment for trolley poles comprising a helical springadapted to be connected to and between separated sections of the pole,the spring having less resistance at its upper than at its lower end.

6. A flexible attachment for trolley poles comprising a helical springadapted to be connected to and between separated sections of the pole,the diameter of the spring being greatest at its'upper end. 7 7. Aflexible attachment for trolley poles comprising a helical springadapted to be connected to and between separated sections of the pole,the spring-coils being quadrilateral in cross section, with the outerperipherynarrower than the inner, said spring being closely coiled;

In testimony whereof I aflix my signature.

FRANK'T. BOGARD.

